The Myers-Briggs personality test: Should you still use it?

The MBTI test is used by countless organizations and industries, but the fact is that its usefulness is not as nearly backed up by evidence as its popularity would suggest.

I was recently trying to find out what kind of personality assessments organizations use to select employees and build teams. The answer that organizations most commonly gave me was the Myers-Briggs Type Indicator (MBTI). It is taken by a mind-boggling number of people that exceeds 2.5 million each year, and is used by a full 89 of the Fortune 100companies. Not only is it considered the world’s most popular psychometric test, but is used for a variety of organizational purposes – from selection, training, and team formation to personal and career coaching.

What is the MBTI?

The MBTI is a battery of 93 questions that sorts respondents into one of 16 personality types. The classification is based on four dichotomies: extraversion – introversion (E-I), sensing – intuition (S-N), thinking – feeling (T-F), and judging- perceiving (J-P). The resulting types are referred to by an abbreviation of four letters. For example, ENTJ describes a person who is outgoing, visionary, analytical, and determined, while ISFP person is quiet, observant, attentive, and flexible. All types have ready made titles, which could easily be printed on a coffee mug or used in tongue-in-cheek name-calling. The ENTJ is the Commander, INFJ is the Counselor, ISFJ is the Protector, and so on. The whole typology can be seen here.

The use of MBTI in psychology has been long abandoned

However, the intriguing, and somewhat alarming, fact about the MBTI is that, despite its overreaching use in organizational settings, its use in psychology has been long abandoned. The test has been a subject of a continuous criticismamong professional psychologists throughout the last three decades and is currently met with open revulsion. There

are sound reasons for this.

MBTI was not developed by scientists

The test was developed in 1940s by the housewife Katherine Briggs and her daughter Isabel Briggs Myers. Briggs was interested in reading biographies and making personality typologies on the basis of patterns she found. After reading Carl Jung’s Psychological Types, she noticed that his theory was similar to her observations. On the basis of Jung’s theory, Briggs and Myers went on to produce a test that would allow women to obtain jobs that suit their personalities. However, neither of them was a trained scientist, and although they were basing the test on Jung’s theories, his psychological types were not developed through controlled scientific studies, but rather via clinical observations and introspection. This is enough to make some people wary.

MBTI is a poor measure of personality

There are two reasons for this. First, and as you can read on the official MBTI site, the test measures personality preferences rather than the actual personality traits. Thus, someone reporting a high score for introversion over extraversion cannot be correctly classified as more introverted; they simply have a clear preference. These are two completely different things.

The test measures personality preferences rather than actual traits

Second, the MBTI assumes that personality falls into mutually exclusive categories. This is incorrect because nobody is 100% extrovert or 100% introvert, just as people are not purely tall or short. Personality, as well as height, should be seen as a continuum, rather than as falling on the either side of an imaginary line. The consequence of this arbitrary classification is that people who are similar, because they are neither particularly extrovert nor introvert, can be categorized as belonging to two completely different personality types.

MBTI is unreliable and rather useless

Additional problem with the test is that it lacks what researchers call “test-retest reliability”. This means that if you take the test again within just few weeks, and answer at least one question differently, there’s around 50% chance that you will fall into a different category. If you were initially categorized as the Performer, now you could easily be the Inspector or the Protector. This makes the testhighly inappropriate for even making intuitive judgments of personality, let alone important life decisions, like which job you should be in. Indeed, research shows that personality types as measured by the MBTI do NOT relate to neither job performance or success within a particular career. Its usefulness in selection procedures, or in providing career advice, is not even doubtful, it’s downright problematic.

Abandon the MBTI and rely on science

In general, the MBTI gives a rather simplified perspective on human personality, which is a concept too complex to be pinned down into dichotomous categories. The scientific study of personality is a valid field, and there are many tools that measure personality with a much greater degree of accuracy. It just happens that the MBTI is not one of them.

Yet, the test is promoted enthusiastically in many workplace settings. Due to expenses involved in the MBTI training (it costs more than €2000 to become a certified administrator!), people tend to believe that the test must be reliable. Moreover, to many, the MBTI makes sense. But so does a horoscope. If you read any potential description of yourself, you are likely to recognize yourself in it. This does not mean that what you read is correct or scientifically valid. Clearly, organizations should turn to scientifically proven assessments, rather than use tools that researchers have long discredited.